What Is Vikram Lander? All You Need To Know About Chandrayaan 3's Vehicle That Will Land On Moon

As per the information on ISRO's website, Chandrayaan-3 consists of an indigenous Lander module (LM), a Propulsion module (PM) and a Rover with the objective of developing and demonstrating new technologies required for Inter planetary missions.

The Vikram lander has been named after Vikram Sarabhai, regarded as the father of the Indian space programme

The Vikram lander has the capability to soft land at a specified lunar site and deploy the Rover which will carry out in-situ chemical analysis of the lunar surface during the course of its mobility.

The Lander and the Rover have scientific payloads to carry out experiments on the lunar surface. The main function of PM is to carry the LM from launch vehicle injection to the final lunar 100 km circular polar orbit and separate the LM from PM.

Apart from this, the Propulsion Module also has one scientific payload as a value addition which will be operated post-separation of Lander Module.

The mission life of Vikram lander and Pragyan rover is one lunar day (~14 Earth days). However, ISRO officials do not rule out the possibility of them coming to life for another lunar day.

To achieve Chandrayaan-3's mission objectives, several advanced technologies are present in Lander such as:

1. Altimeters: Laser & RF based Altimeters

2. Velocimeters: Laser Doppler Velocimeter & Lander Horizontal Velocity Camera

3. Inertial Measurement: Laser Gyro based Inertial referencing and Accelerometer package

4. Propulsion System: 800N Throttleable Liquid Engines, 58N attitude thrusters & Throttleable Engine Control Electronics

5. Navigation, Guidance & Control (NGC): Powered Descent Trajectory design and associate software elements

6. Hazard Detection and Avoidance: Lander Hazard Detection & Avoidance Camera and Processing Algorithm

7. Landing Leg Mechanism.

The module would undergo internal checks and await the sun-rise at the designated landing site, ISRO has said, adding that the powered descent -- to achieve soft-landing on the Moon's surface -- is expected to be initiated at around 5:45 pm on Wednesday.

According to PTI, the critical process of soft-landing has been dubbed by many including ISRO officials as '17 minutes of terror', with the entire process being autonomous when the lander has to fire its engines at the right times and altitudes, use the right amount of fuel, and scan of the lunar surface for any obstacles or hills or craters before finally touching down.

After checking all the parameters and deciding to land, ISRO will upload all the required commands from its Indian Deep Space Network (IDSN) at Byalalu near Bengaluru, to the LM, a couple of hours before the scheduled time touchdown.

ISRO Chairman S Somanath had recently said the most critical part of the landing will be the process of reducing the velocity of the lander from 30km height to the final landing, and the ability to reorient the spacecraft from horizontal to vertical direction.

"This is the trick we have to play here," he said.

(With PTI inputs)